1. Field of the Invention
The present invention relates to a home network system for controlling one or more home appliances over a wired- or wireless-network implemented in a building, and more particularly to a home network system and a method for operating the same, which can automatically recognize a network connection state of the home appliance even though a network manager for controlling the flow of signals over the network abnormally receives an alive message or a connection-termination message from one or more home appliances connected or unconnected to the network, and can update a network information DB (database), resulting in increased reliability of control operations of the home appliance.
2. Description of the Related Art
FIG. 1 is a conceptual diagram illustrating a conventional home network system.
Referring to FIG. 1, a network N has been implemented in a building, and has widely used a variety of lines, for example, power lines and LAN (Local Area Network) lines, etc.
One or more home appliances C1˜C4, and a home server HS for centrally controlling the home appliances C1˜C4 are interconnected over the network to establish data communication between the home appliances C1˜C4 and the home server HS, such that the home server HS can control operations of the home appliances C1˜C4, and can monitor their states.
For example, the home appliances C1˜C4 may be determined to be a washing machine, a microwave oven, and a TV, etc., and is indicative of a home appliance capable of performing a corresponding operation upon receiving a control signal from the home server HS.
The home server HS act as a server for controlling the flow of signals communicating with the network N, can centrally control operations of the home appliances C1˜C4, and can also monitor states of the home appliances C1˜C4. It should be noted that the home server HS is substantially equal to a network manager.
As shown in FIG. 1, an Internet refrigerator operated to perform predetermined signal processing operations 24 hours a day is adapted as a server for illustrative purposes.
In this case, if the home appliances C1˜C4 are initially connected to the network N, they transmit an alive message informing the network N of the initial connection to a network manager HS.
If the home appliances C1˜C4 are disconnected from the network, a connection termination message informing the network N of the non-connection state is transmitted to the network manager HS, such that a user can easily recognize network connection states of individual home appliances using the network manager HS.
If the network N is implemented with a wired network, the alive message or the connection termination message having been received from the home appliances C1˜C4 can be transmitted to the network manager HS without losing data on a transmission path at high success probability. If the network N is implemented with a wireless network, it has different transmission rates according to variable communication network states, and considerably reduces the probability of transmitting data to the network manager HS due to noise.
In more detail, if the home appliances C1˜C4 are initially connected to or disconnected from the network when a wireless network such as a wireless LAN (Local Area Network) is used, an alive message or a connection termination message is wirelessly transmitted to the network manager HS.
However, the message wirelessly transmitted from the home appliances C1˜C4 may encounter transmission delay or loss data according to wireless communication network state information, such that the network manager HS cannot correctly recognize whether the home appliances are connected to or disconnected from the network.
The aforementioned problems unavoidably arise even when the network N is configured in the form of power lines. Particularly, it is impossible to block signal transmission between neighbors, the conventional home network system cannot transmit the alive message or the connection termination message to the corresponding network manager HS in a building causing mutual interference of signals, resulting in reduced control reliability.
Also, even in the case of using power lines connected to the network N, the home appliances cannot transmit the connection termination message to the home server home-appliance HS when the connection between the home appliances C1˜C4 and the network is compulsorily severed because power lines of the home appliances C1˜C4 are disconnected from a power-supply socket receiving power source, such that the network manager cannot recognize a non-connection state between the home appliances and the network.